quarkusio/quarkus · error · RuntimeException

Failed to log the dependency tree to a file

Error message

Failed to log the dependency tree to a file

What it means

DependencyTreeMojo writes the dependency tree output through a consumer lambda that wraps a BufferedWriter. If writing a line to the target file throws an IOException, the lambda wraps it in a RuntimeException with this message. The goal was asked to write the tree to a file but the file could not be written.

Source

Thrown at devtools/maven/src/main/java/io/quarkus/maven/DependencyTreeMojo.java:118

        if (outputFile == null) {
            log = s -> getLog().info(s);
        } else {
            final BufferedWriter bw;
            try {
                Files.createDirectories(outputFile.toPath().getParent());
                final OpenOption[] openOptions = appendOutput && outputFile.exists()
                        ? new OpenOption[] { StandardOpenOption.APPEND }
                        : new OpenOption[0];
                bw = writer = Files.newBufferedWriter(outputFile.toPath(), openOptions);
            } catch (IOException e) {
                throw new MojoExecutionException("Failed to initialize file output writer", e);
            }
            log = s -> {
                try {
                    bw.write(s);
                    bw.newLine();
                } catch (IOException e) {
                    throw new RuntimeException("Failed to log the dependency tree to a file", e);
                }
            };
        }
        try {
            logTree(log);
        } finally {
            if (writer != null) {
                try {
                    writer.close();
                } catch (IOException e) {
                    getLog().debug("Failed to close the output file", e);
                }
            }
        }
    }

    private void logTree(final Consumer<String> log) throws MojoExecutionException {
        log.accept("Quarkus application " + mode.toUpperCase() + " mode build dependency tree:");

View on GitHub (pinned to e1c734241f)

Solutions

1. Check that the directory containing the output file exists and is writable (create it with mkdir -p / chmod).
2. Close any process holding the output file open, or choose a different output file path.
3. Free disk space if the filesystem is full.
4. Run the goal from a directory where the current user has write permissions instead of a system location.

Example fix

// before
mvn quarkus:dependency-tree -DoutputFile=/proc/out.txt
// after
mkdir -p target/reports && mvn quarkus:dependency-tree -DoutputFile=target/reports/deptree.txt

// before running: ensure output location is writable
Path out = Path.of("target/deptree.txt");
Files.createDirectories(out.getParent());
if (!Files.isWritable(out.getParent())) throw new IllegalStateException("Output dir not writable: " + out.getParent());

When it happens

Trigger: Running `mvn quarkus:dependency-tree` where the log consumer writes to a file whose path is unwritable, the parent directory does not exist, the file is locked by another process, or the disk is full.

Common situations: Output file placed in a read-only directory; parent directory not created; another process (tail, editor, previous crashed build) holds a lock on the file; full disk on CI; Windows file handle still open from a prior run.

Understand the failure class

Background: "Permission denied" / "Failed to write" file errors: why a library can't write its files to disk (EACCES, EPERM, ENOSPC) and how to fix them — this error's family across 43 libraries.

Related errors

• Failed to initialize file output writer
• Failed to log the dependency list to a file
• Failed to initialize file output writer
• Unable to write quarkus native image agent caller filter to
• Failed to read ${compareFile}

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/dfbbd1a5b0eb9cc2. Report an issue: GitHub.